TPS2045, TPS2055
CURRENT-LIMITED POWER-DISTRIBUTION SWITCHES
SLVS182 – APRIL 1999
features
typical applications
135-mΩ -Maximum (5-V Input) High-Side
MOSFET Switch
Notebook, Desktop and Palmtop PCs
Monitors, Keyboards, Scanners, and
Printers
250 mA Continuous Current
Short-Circuit and Thermal Protection With
Overcurrent Logic Output
Digital Cameras, Phones, and PBXs
Hot-Insertion Applications
Operating Range . . . 2.7-V to 5.5-V
Logic-Level Enable Input
TPS2045
D OR P PACKAGE
(TOP VIEW)
TPS2055
D OR P PACKAGE
(TOP VIEW)
2.5-ms Typical Rise Time
Undervoltage Lockout
GND
IN
OUT
OUT
OUT
OC
GND
IN
OUT
OUT
OUT
OC
1
2
3
4
8
7
6
5
1
2
3
4
8
7
6
5
10 µA Maximum Standby Supply Current
Bidirectional Switch
IN
IN
Available in 8-pin SOIC and PDIP Packages
Ambient Temperature Range, –40°C to 85°C
EN
EN
2-kV Human-Body-Model, 200-V
Machine-Model ESD Protection
description
The TPS2045 and TPS2055 power-distribution switches are intended for applications where heavy capacitive
loads and short circuits are likely. Each of these 135-mΩ N-channel MOSFET high-side power switches is
controlledbyalogicenablecompatiblewith5-Vand3-Vlogic. Gatedriveisprovidedbyaninternalchargepump
that controls the power-switch rise times and fall times to minimize current surges during switching. The charge
pump requires no external components and allows operation from supplies as low as 2.7 V.
When the output load exceeds the current-limit threshold or a short is present, the TPS2045 and TPS2055 limit
the output current to a safe level by switching into a constant-current mode, pulling the overcurrent (OC) logic
output low. When continuous heavy overloads and short circuits increase the power dissipation in the switch,
causingthejunctiontemperaturetorise, athermalprotectioncircuitshutsofftheswitchinovercurrenttoprevent
damage. Recovery from a thermal shutdown is automatic once the device has cooled sufficiently. Internal
circuitry ensures the switch remains off until valid input voltage is present.
The TPS2045 and TPS2055 are designed to limit at 0.44-A load. These power-distribution switches, available
in 8-pin small-outline integrated circuit (SOIC) and 8-pin plastic dual-in-line packages (PDIP), operate over an
ambient temperature range of –40°C to 85°C.
AVAILABLE OPTIONS
RECOMMENDED
MAXIMUM CONTINUOUS
LOAD CURRENT
(A)
PACKAGED DEVICES
TYPICAL SHORT-CIRCUIT
CURRENT LIMIT AT 25°C
(A)
T
A
ENABLE
SOIC
PDIP
(P)
†
(D)
–40°C to 85°C Active low
–40°C to 85°C Active high
0.25
0.25
0.44
0.44
TPS2045D TPS2045P
TPS2055D TPS2055P
†
The D package is available taped and reeled. Add an R suffix to device type (e.g., TPS2045DR)
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
Copyright 1999, Texas Instruments Incorporated
This document contains information on products in more than one phase
of development. The status of each device is indicated on the page(s)
specifying its electrical characteristics.
1
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